Like the Corvette ZR-1 you could fabricate the two Camaro sub-frames in something other than steel to get the weight down quite a bit. They did the ZR-1 frame in aluminum to save weight. Just a thought.

I bet you could get 20-40 lbs out of subframes using lighter materials...but they'd need to be totally redesigned and stress-tested, validated, etc to ensure performance-to-spec. Different materials have different torsional, and tensile characteristics.

An aluminum frame is a good thought...however, the Camaro is unibody, which the Corvette isn't...not really; they call it a 'spaceframe' design. And once they were done? They saved a grand total of ~150 lbs...Certain Camaro design features, such as the rear 'shoulders'...cannot be stamped in aluminum. It was hard enough to figure out how to stamp them in steel. It becomes prohibitively expensive to try and engineer/build a unibody as complex and strong as the Camaro's out of aluminum.

They'll have to tackle these questions on the next generation...the number one way to reduce weight without exorbitant expense would be to shrink it's size. Then worry about exotic materials...